InformationWeek says that invitations sent out by Microsoft yesterday have confirmed the date for the Windows 8 preview as February 29, 2012. Microsoft will hold an event in Barcelona, Spain, on Feb. 29 to formally launch Windows 8 Consumer Preview, according to an invitation the company sent to journalists Wednesday. The date and location coincide with the World Mobile Congress, an indication that Microsoft is serious about pushing Windows 8 as a mobile operating system for tablets, as well as for traditional desktops and laptops.